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matlabgraphfigure

Why my code produce an incorrect graph in MATLAB?

Does anyone know why my MATLAB code is give an incorrect graph?

I want to plot f(x)=exp(-x)-2*x.

The codes as follows.

clear all;
clc;
h=0.01;
x=-1:h:1;
f=exp(-x)-2*x;
plot(f,x,'color','r');
grid on;
xlabel('x');
ylabel('y');

This code give me a figure like this.

enter image description here

We know f(0)=1. But in the graph f(0) not equal to 1. Does anyone know why my code produce an incorrect graph?

Solution

  • The axis on your graph are inverted. The line that says

    plot(f,x,'color','r');

    should be:

    plot(x,f,'color','r');

    The plot function expects first the abscissa (x) and then the ordinate (f).